static void
scan_curchan_task(void *arg, int pending)
{
struct ieee80211_scan_state *ss = arg;
struct scan_state *ss_priv = SCAN_PRIVATE(ss);
struct ieee80211com *ic = ss->ss_ic;
struct ieee80211_channel *chan;
unsigned long maxdwell;
int scandone;
IEEE80211_LOCK(ic);
end:
scandone = (ss->ss_next >= ss->ss_last) ||
(ss_priv->ss_iflags & ISCAN_CANCEL) != 0;
IEEE80211_DPRINTF(ss->ss_vap, IEEE80211_MSG_SCAN,
"%s: loop start; scandone=%d\n",
__func__,
scandone);
if (scandone || (ss->ss_flags & IEEE80211_SCAN_GOTPICK) ||
(ss_priv->ss_iflags & ISCAN_ABORT) ||
ieee80211_time_after(ticks + ss->ss_mindwell, ss_priv->ss_scanend)) {
ss_priv->ss_iflags &= ~ISCAN_RUNNING;
scan_end(ss, scandone);
return;
} else
ss_priv->ss_iflags |= ISCAN_RUNNING;
chan = ss->ss_chans[ss->ss_next++];
/*
* Watch for truncation due to the scan end time.
*/
if (ieee80211_time_after(ticks + ss->ss_maxdwell, ss_priv->ss_scanend))
maxdwell = ss_priv->ss_scanend - ticks;
else
maxdwell = ss->ss_maxdwell;
IEEE80211_DPRINTF(ss->ss_vap, IEEE80211_MSG_SCAN,
"%s: chan %3d%c -> %3d%c [%s, dwell min %lums max %lums]\n",
__func__,
ieee80211_chan2ieee(ic, ic->ic_curchan),
ieee80211_channel_type_char(ic->ic_curchan),
ieee80211_chan2ieee(ic, chan),
ieee80211_channel_type_char(chan),
(ss->ss_flags & IEEE80211_SCAN_ACTIVE) &&
(chan->ic_flags & IEEE80211_CHAN_PASSIVE) == 0 ?
"active" : "passive",
ticks_to_msecs(ss->ss_mindwell), ticks_to_msecs(maxdwell));
/*
* Potentially change channel and phy mode.
*/
ic->ic_curchan = chan;
ic->ic_rt = ieee80211_get_ratetable(chan);
IEEE80211_UNLOCK(ic);
/*
* Perform the channel change and scan unlocked so the driver
* may sleep. Once set_channel returns the hardware has
* completed the channel change.
*/
ic->ic_set_channel(ic);
ieee80211_radiotap_chan_change(ic);
/*
* Scan curchan. Drivers for "intelligent hardware"
* override ic_scan_curchan to tell the device to do
* the work. Otherwise we manage the work ourselves;
* sending a probe request (as needed), and arming the
* timeout to switch channels after maxdwell ticks.
*
* scan_curchan should only pause for the time required to
* prepare/initiate the hardware for the scan (if at all).
*/
ic->ic_scan_curchan(ss, maxdwell);
IEEE80211_LOCK(ic);
/* XXX scan state can change! Re-validate scan state! */
ss_priv->ss_chanmindwell = ticks + ss->ss_mindwell;
/* clear mindwell lock and initial channel change flush */
ss_priv->ss_iflags &= ~ISCAN_REP;
if (ss_priv->ss_iflags & (ISCAN_CANCEL|ISCAN_ABORT)) {
taskqueue_cancel_timeout(ic->ic_tq, &ss_priv->ss_scan_curchan,
NULL);
goto end;
}
IEEE80211_DPRINTF(ss->ss_vap, IEEE80211_MSG_SCAN, "%s: waiting\n",
__func__);
IEEE80211_UNLOCK(ic);
}
static void
scan_task(void *arg, int pending)
{
#define ISCAN_REP (ISCAN_MINDWELL | ISCAN_DISCARD)
struct ieee80211_scan_state *ss = (struct ieee80211_scan_state *) arg;
struct ieee80211vap *vap = ss->ss_vap;
struct ieee80211com *ic = ss->ss_ic;
struct ieee80211_channel *chan;
unsigned long maxdwell, scanend;
int scandone = 0;
IEEE80211_LOCK(ic);
if (vap == NULL || (ic->ic_flags & IEEE80211_F_SCAN) == 0 ||
(SCAN_PRIVATE(ss)->ss_iflags & ISCAN_ABORT)) {
/* Cancelled before we started */
goto done;
}
if (ss->ss_next == ss->ss_last) {
IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
"%s: no channels to scan\n", __func__);
goto done;
}
if (vap->iv_opmode == IEEE80211_M_STA &&
vap->iv_state == IEEE80211_S_RUN) {
if ((vap->iv_bss->ni_flags & IEEE80211_NODE_PWR_MGT) == 0) {
/* Enable station power save mode */
ieee80211_sta_pwrsave(vap, 1);
/*
* Use an 1ms delay so the null data frame has a chance
* to go out.
* XXX Should use M_TXCB mechanism to eliminate this.
*/
cv_timedwait(&SCAN_PRIVATE(ss)->ss_scan_cv,
IEEE80211_LOCK_OBJ(ic), hz / 1000);
if (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_ABORT)
goto done;
}
}
scanend = ticks + SCAN_PRIVATE(ss)->ss_duration;
IEEE80211_UNLOCK(ic);
ic->ic_scan_start(ic); /* notify driver */
IEEE80211_LOCK(ic);
for (;;) {
scandone = (ss->ss_next >= ss->ss_last) ||
(SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) != 0;
if (scandone || (ss->ss_flags & IEEE80211_SCAN_GOTPICK) ||
(SCAN_PRIVATE(ss)->ss_iflags & ISCAN_ABORT) ||
time_after(ticks + ss->ss_mindwell, scanend))
break;
chan = ss->ss_chans[ss->ss_next++];
/*
* Watch for truncation due to the scan end time.
*/
if (time_after(ticks + ss->ss_maxdwell, scanend))
maxdwell = scanend - ticks;
else
maxdwell = ss->ss_maxdwell;
IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
"%s: chan %3d%c -> %3d%c [%s, dwell min %lums max %lums]\n",
__func__,
ieee80211_chan2ieee(ic, ic->ic_curchan),
channel_type(ic->ic_curchan),
ieee80211_chan2ieee(ic, chan), channel_type(chan),
(ss->ss_flags & IEEE80211_SCAN_ACTIVE) &&
(chan->ic_flags & IEEE80211_CHAN_PASSIVE) == 0 ?
"active" : "passive",
ticks_to_msecs(ss->ss_mindwell), ticks_to_msecs(maxdwell));
/*
* Potentially change channel and phy mode.
*/
ic->ic_curchan = chan;
ic->ic_rt = ieee80211_get_ratetable(chan);
IEEE80211_UNLOCK(ic);
/*
* Perform the channel change and scan unlocked so the driver
* may sleep. Once set_channel returns the hardware has
* completed the channel change.
*/
ic->ic_set_channel(ic);
ieee80211_radiotap_chan_change(ic);
/*
* Scan curchan. Drivers for "intelligent hardware"
* override ic_scan_curchan to tell the device to do
* the work. Otherwise we manage the work outselves;
* sending a probe request (as needed), and arming the
* timeout to switch channels after maxdwell ticks.
*
* scan_curchan should only pause for the time required to
* prepare/initiate the hardware for the scan (if at all), the
* below condvar is used to sleep for the channels dwell time
* and allows it to be signalled for abort.
*/
ic->ic_scan_curchan(ss, maxdwell);
IEEE80211_LOCK(ic);
SCAN_PRIVATE(ss)->ss_chanmindwell = ticks + ss->ss_mindwell;
/* clear mindwell lock and initial channel change flush */
SCAN_PRIVATE(ss)->ss_iflags &= ~ISCAN_REP;
if ((SCAN_PRIVATE(ss)->ss_iflags & (ISCAN_CANCEL|ISCAN_ABORT)))
continue;
/* Wait to be signalled to scan the next channel */
cv_wait(&SCAN_PRIVATE(ss)->ss_scan_cv, IEEE80211_LOCK_OBJ(ic));
}
if (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_ABORT)
goto done;
IEEE80211_UNLOCK(ic);
ic->ic_scan_end(ic); /* notify driver */
IEEE80211_LOCK(ic);
/*
* Record scan complete time. Note that we also do
* this when canceled so any background scan will
* not be restarted for a while.
*/
if (scandone)
ic->ic_lastscan = ticks;
/* return to the bss channel */
if (ic->ic_bsschan != IEEE80211_CHAN_ANYC &&
ic->ic_curchan != ic->ic_bsschan) {
ieee80211_setupcurchan(ic, ic->ic_bsschan);
IEEE80211_UNLOCK(ic);
ic->ic_set_channel(ic);
ieee80211_radiotap_chan_change(ic);
IEEE80211_LOCK(ic);
}
/* clear internal flags and any indication of a pick */
SCAN_PRIVATE(ss)->ss_iflags &= ~ISCAN_REP;
ss->ss_flags &= ~IEEE80211_SCAN_GOTPICK;
/*
* If not canceled and scan completed, do post-processing.
* If the callback function returns 0, then it wants to
* continue/restart scanning. Unfortunately we needed to
* notify the driver to end the scan above to avoid having
* rx frames alter the scan candidate list.
*/
if ((SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) == 0 &&
!ss->ss_ops->scan_end(ss, vap) &&
(ss->ss_flags & IEEE80211_SCAN_ONCE) == 0 &&
time_before(ticks + ss->ss_mindwell, scanend)) {
IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
"%s: done, restart "
"[ticks %u, dwell min %lu scanend %lu]\n",
__func__,
ticks, ss->ss_mindwell, scanend);
ss->ss_next = 0; /* reset to begining */
if (ss->ss_flags & IEEE80211_SCAN_ACTIVE)
vap->iv_stats.is_scan_active++;
else
vap->iv_stats.is_scan_passive++;
ss->ss_ops->scan_restart(ss, vap); /* XXX? */
ieee80211_runtask(ic, &SCAN_PRIVATE(ss)->ss_scan_task);
IEEE80211_UNLOCK(ic);
return;
}
/* past here, scandone is ``true'' if not in bg mode */
if ((ss->ss_flags & IEEE80211_SCAN_BGSCAN) == 0)
scandone = 1;
IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
"%s: %s, [ticks %u, dwell min %lu scanend %lu]\n",
__func__, scandone ? "done" : "stopped",
ticks, ss->ss_mindwell, scanend);
/*
* Clear the SCAN bit first in case frames are
* pending on the station power save queue. If
* we defer this then the dispatch of the frames
* may generate a request to cancel scanning.
*/
done:
ic->ic_flags &= ~IEEE80211_F_SCAN;
/*
* Drop out of power save mode when a scan has
* completed. If this scan was prematurely terminated
* because it is a background scan then don't notify
* the ap; we'll either return to scanning after we
* receive the beacon frame or we'll drop out of power
* save mode because the beacon indicates we have frames
* waiting for us.
*/
if (scandone) {
ieee80211_sta_pwrsave(vap, 0);
if (ss->ss_next >= ss->ss_last) {
ieee80211_notify_scan_done(vap);
ic->ic_flags_ext &= ~IEEE80211_FEXT_BGSCAN;
}
}
SCAN_PRIVATE(ss)->ss_iflags &= ~(ISCAN_CANCEL|ISCAN_ABORT);
ss->ss_flags &= ~(IEEE80211_SCAN_ONCE | IEEE80211_SCAN_PICK1ST);
IEEE80211_UNLOCK(ic);
#undef ISCAN_REP
}